Phosphotungstic acid - Jeffamine® hybrid catalyst for one-pot Biginelli reaction starting from benzyl alcohol

Efficient conversion of Biginelli product in one-pot one-step process with Phosphotungstic acid immobilized over Jeffamine as supported catalyst. [Display omitted] •First time report of Biginelli reaction at almost neutral pH (7.5) in aqueous medium in a one-pot one-step process.•One-pot one-step protocol demonstrated appreciable yield (87%) of DHPM within 5.5 h at pH 7.5.•The catalyst was easily separated from the products though a simple freezing process.•DHPM obtained from the one-pot two-step process demonstrated anti-cancer activities.•The use of hydrogen peroxide as oxidant deserves a special mention in the present manuscript.•The manuscript may pave ways to the development of industrial catalysts and environmentally friendly reaction protocols. Herein, we report the catalytic action of phosphotungstic acid - Jeffamine® hybrid (PTA-Jeffamine®) for the synthesis of dihydropyrimidinones (DHPMs) starting from benzyl alcohol by Biginelli reaction in water in a one-pot system. Hydrogen peroxide was used as oxidizing agent instead of the conventional nitrate salts. A two-step and a one-step protocol was used to evaluate the catalytic activity. Both processes showed appreciable results with the one-pot one-step protocol demonstrating appreciable yield (87 %) of DHPM within 5.5 h at pH 7.5. No acid was added and the pH was adjusted by controlling ratio of PTA/ Jeffamine®. Catalytic results were compared with literature reports for one-pot one-step Biginelli reactions starting from benzyl alcohol. Biginelli products were characterized by UV-visle–vis, FT-IR, NMR spectroscopy. DHPMs formed from the two-step process demonstrated appreciable anticancer activity. The present work may lead to the development of industry-friendly, non-toxic and scalable catalyst for one-pot Biginelli reactions.